<template>
  <div class="login_container">
    <div class="login_box">
      <!-- 头像区域 -->
      <div class="avatar_box">
        <img src="../assets/logo.png" alt="" />
      </div>
      <!-- 登录表单区域 -->
      <el-form
        ref="loginFormRef"
        label-width="0px"
        class="login_form"
        :model="loginForm"
        :rules="loginFormRules">
        <!-- 用户名 -->
        <el-form-item prop="username">
          <el-input
            v-model="loginForm.username"
            prefix-icon="el-icon-user"
          ></el-input>
        </el-form-item>
        <!-- 密码 -->
        <el-form-item prop="password">
          <el-input
            show-password
            v-model="loginForm.password"
            prefix-icon="el-icon-goods"
          ></el-input>
        </el-form-item>
        <!-- 按钮 -->
        <el-form-item class="btns">
          <el-button type="primary" @click="login">登录</el-button>
          <el-button type="info" @click="resetLoginForm">重置</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>

<script>
export default {
  name: 'Login',
  data() {
    return {
      // 登录表单的数据绑定
      loginForm: {
        username: 'admin',
        password: '123456',
      },
      // 表单的验证规则
      loginFormRules: {
        // 验证用户名是否正确
        username: [
          { required: true, message: '请输入用户名称', trigger: 'blur' },
          { min: 3, max: 6, message: '长度在 3 到 6 个字符', trigger: 'blur' },
        ],
        // 验证密码是否正确
        password: [
          { required: true, message: '请输入密码', trigger: 'blur' },
          {
            min: 6,
            max: 16,
            message: '长度在 6 到 16 个字符',
            trigger: 'blur',
          },
        ],
      },
    }
  },
  methods: {
    // 表单的resetFields方法: 重置登录表单
    resetLoginForm() {
      this.$refs.loginFormRef.resetFields()
    },
    // 表单的validate方法：登录验证
    login() {
      this.$refs.loginFormRef.validate(async valid => {
        if (!valid) return
        const { data: res } = await this.$http.post('login', this.loginForm)
        //console.log(res)
        if (res.meta.status !== 200) return this.$message.error('登陆失败')
        this.$message.success('登陆成功')
        /* 登陆成功后将token保存到客户端的sessionStorage中
        token应该在当前网站打开期间生效,故使用sessionStorage
        项目中除了登陆之外的其它api接口，必须在登陆后才能访问 */
        window.sessionStorage.setItem('token', res.data.token)
        // 通过编程式导航跳转到后台主页，路由地址：/home
        this.$router.push('/home')
      })
    },
  },
}
</script>

<style lang="less" scoped>
.login_container {
  background-color: #2b4d6e;
  height: 100%;
}
.login_box {
  width: 450px;
  height: 300px;
  background-color: #fff;
  border-radius: 5px;
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);

  .avatar_box {
    width: 130px;
    height: 130px;
    border: 1px solid #eee;
    border-radius: 50%;
    padding: 8px;
    box-shadow: 0 0 6px #ddd;
    background-color: #fff;
    position: absolute;
    left: 50%;
    transform: translate(-50%, -35%);
    img {
      width: 100%;
      height: 100%;
      border-radius: 50%;
      background-color: #eee;
    }
  }
}
.login_form {
  position: absolute;
  bottom: 0;
  width: 100%;
  padding: 0 20px;
  box-sizing: border-box;
}
.btns {
  display: flex;
  justify-content: flex-end;
}
</style>